Cleanliness and cleanability are two important objectives in the food processing industry involving food pasteurization. A problem area in this regard is the vacuum breaker, a representative drawing of which is shown in FIG. 6. The vacuum breaker will be placed between the raw material and the holding tank, for example, and when the system is shut down, it is important that the material in the connecting conduit be allowed to return by gravity to either the raw material source, if it has not been processed, and if it has been processed, moved on to the holding tank. It is important that unprocessed, raw material not flow on to the holding tank. Vacuum breakers currently being used do not have openings for draining material on the atmosphere side of the valve to the outside of the valve.
The operation of the vacuum breaker valve should be positive and the valve should be maintained in a normally closed position and adapted to open only when the system is shut down. The conventional vacuum breaker used in this industry suffers from not providing a positive shut-off when the system is operating, thereby allowing material being processed to flow through the valve and be splattered all over it and outside the valve. The cleaning on the inside and outside of the vacuum breaker valve is a continuous, ongoing chore. A particular problem is that material being processed accumulates on the atmosphere side of the valve element and the cover must be removed to clean the valve. If this material is not removed from the atmosphere side of the valve, it will then drain back into the food processing conduit, thereby contaminating the food being processed.